## 预约挂号系统微服务搭建 ### 1.构建父工程(yygh_parent) #### 1.1 Spring initializer构建父工程  #### 1.2添加配置pom.xml pom.xml的配置主要是修改SpringBoot的版本，IDEA创建的版本太新，不合适，因此，版本修改为2.2.1.RELEASE。另外锁定版本依赖，例如java、cloud、mybatis-plus等，这样方便进行统一管理。还有一些依赖。 ```xml <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <modules> <module>common</module> <module>model</module> <module>service</module> </modules> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.2.1.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.zjk</groupId> <artifactId>yygh_parent</artifactId> <packaging>pom</packaging> <version>0.0.1-SNAPSHOT</version> <name>yygh_parent</name> <description>yygh_parent</description> <properties> <java.version>1.8</java.version> <cloud.version>Hoxton.RELEASE</cloud.version> <alibaba.version>2.2.0.RELEASE</alibaba.version> <mybatis-plus.version>3.3.1</mybatis-plus.version> <mysql.version>8.0.26</mysql.version> <swagger.version>2.7.0</swagger.version> <jwt.version>0.7.0</jwt.version> <fast.json.version>1.2.29</fast.json.version> <httppclient.versin>4.5.1</httppclient.versin> <easyexecl.version>2.2.0-beta2</easyexecl.version> <aliyun.version>4.1.1</aliyun.version> <oss.version>3.9.1</oss.version> <jodatime.version>2.10.1</jodatime.version> </properties> <!--配置dependencyManagement锁定依赖版本--> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-dependencies</artifactId> <version>${cloud.version}</version> <type>pom</type> <scope>import</scope> </dependency> <dependency> <groupId>com.alibaba.cloud</groupId> <artifactId>spring-cloud-alibaba-dependencies</artifactId> <version>${alibaba.version}</version> <type>pom</type> <scope>import</scope> </dependency> <!--mybatis-plus 持久层--> <dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-boot-starter</artifactId> <version>${mybatis-plus.version}</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>${mysql.version}</version> </dependency> <!-- https://mvnrepository.com/artifact/com.github.xiaoymin/knife4j-spring-boot-starter --> <dependency> <groupId>com.github.xiaoymin</groupId> <artifactId>knife4j-spring-boot-starter</artifactId> <version>${swagger.version}</version> </dependency> <dependency> <groupId>io.jsonwebtoken</groupId> <artifactId>jjwt</artifactId> <version>${jwt.version}</version> </dependency> <dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>httpclient</artifactId> <version>${httpclient.version}</version> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> <version>${fastjson.version}</version> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>easyexcel</artifactId> <version>${easyexcel.version}</version> </dependency> <dependency> <groupId>com.aliyun</groupId> <artifactId>aliyun-java-sdk-core</artifactId> <version>${aliyun.version}</version> </dependency> <dependency> <groupId>com.aliyun.oss</groupId> <artifactId>aliyun-sdk-oss</artifactId> <version>${oss.version}</version> </dependency> <!--日期时间工具--> <dependency> <groupId>joda-time</groupId> <artifactId>joda-time</artifactId> <version>${jodatime.version}</version> </dependency> </dependencies> </dependencyManagement> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project> ``` ### 2.搭建common父模块 #### 2.1 利用maven构建（后续的模块的构建，操作相同，不一一展示）  #### 2.2修改配置pom.xml (主要是添加依赖) ```xml <dependencies> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> </dependency> <!--mybatis-plus--> <dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-boot-starter</artifactId> <scope>provided </scope> </dependency> <!--swagger--> <dependency> <groupId>io.springfox</groupId> <artifactId>springfox-swagger2</artifactId> <scope>provided </scope> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>easyexcel</artifactId> <scope>provided </scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-mongodb</artifactId> <scope>provided </scope> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> <scope>provided </scope> </dependency> </dependencies> ``` ### 3.构建common_util模块 #### 3.2修改配置pom.xml (主要是添加依赖) ```xml <dependencies> <dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>httpclient</artifactId> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> </dependency> <dependency> <groupId>io.jsonwebtoken</groupId> <artifactId>jjwt</artifactId> </dependency> <dependency> <groupId>com.alibaba</groupId> <artifactId>easyexcel</artifactId> </dependency> <dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-generator</artifactId> <version>3.4.1</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> </dependency> <dependency> <groupId>org.apache.velocity</groupId> <artifactId>velocity-engine-core</artifactId> <version>2.0</version> </dependency> <!-- 日期工具栏依赖 --> <dependency> <groupId>joda-time</groupId> <artifactId>joda-time</artifactId> </dependency> </dependencies> ``` ### 4.构建service_util模块 #### 4.2修改配置pom.xml (主要是添加依赖) ``` <dependencies> <dependency> <groupId>com.atguigu</groupId> <artifactId>common_util</artifactId> <version>1.0</version> </dependency> <!-- redis --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-redis</artifactId> </dependency> <!-- spring2.X集成redis所需common-pool2--> <dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-pool2</artifactId> <version>2.6.0</version> </dependency> </dependencies> ``` ### 5.构建service父模块 #### 5.2修改配置pom.xml (主要是添加依赖) ``` <!--web--> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <!--mybatis-plus--> <dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-boot-starter</artifactId> </dependency> <!--mysql--> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> </dependency> <!--开发者工具--> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-devtools</artifactId> <optional>true</optional> </dependency> <!-- 服务调用feign --> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-openfeign</artifactId> </dependency> <!-- SpringCloud Feign在Hoxton.M2 RELEASED版本之后不再使用Ribbon而是使用spring-cloud-loadbalancer， 所以不引入spring-cloud-loadbalancer会报错 --> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-loadbalancer</artifactId> </dependency> <!-- 服务注册 --> <dependency> <groupId>com.alibaba.cloud</groupId> <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId> </dependency> <!-- <!– 流量控制 –>--> <!-- <dependency>--> <!-- <groupId>com.alibaba.cloud</groupId>--> <!-- <artifactId>spring-cloud-starter-alibaba-sentinel</artifactId>--> <!-- </dependency>--> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> <resources> <resource> <directory>src/main/java</directory> <includes> <include>**/*.yaml</include> <include>**/*.properties</include> <include>**/*.xml</include> </includes> <filtering>false</filtering> </resource> </resources> </build> ``` 最后删除父模块下的src文件夹，只保留子模块下的src文件。模块结构如图所示：  预约挂号系统微服务模块构建工程就完成了。 ### 补充： #### 什么是微服务？ 微服务是一种开发软件的架构和组织方法，其中软件由通过明确定义的 API 进行通信的小型独立服务组成。这些服务由各个小型独立团队负责。 微服务架构使应用程序更易于扩展和更快地开发，从而加速创新并缩短新功能的上市时间。 #### 整体式架构与微服务架构的却必然 通过整体式架构，所有进程紧密耦合，并可作为单项服务运行。这意味着，如果应用程序的一个进程遇到需求峰值，则必须扩展整个架构。随着代码库的增长，添加或改进整体式应用程序的功能变得更加复杂。这种复杂性限制了试验的可行性，并使实施新概念变得困难。整体式架构增加了应用程序可用性的风险，因为许多依赖且紧密耦合的进程会扩大单个进程故障的影响。  使用微服务架构，将应用程序构建为独立的组件，并将每个应用程序进程作为一项服务运行。这些服务使用轻量级 API 通过明确定义的接口进行通信。这些服务是围绕业务功能构建的，每项服务执行一项功能。由于它们是独立运行的，因此可以针对各项服务进行更新、部署和扩展，以满足对应